In the United States, Mr. Green was best known as the composer of “Black Magic Woman,” which he first performed two years before it became an international hit for Carlos Santana. In his native England, he was revered as perhaps the finest rock guitarist of his generation, ranked on the same level as Eric Clapton and Led Zeppelin’s Jimmy Page.
Mr. Green was a charismatic figure at the forefront of a fast-moving rock-and-roll revolution, as the music evolved in the late 1960s from its blues-based origins to a more ornate and theatrical style, with overtones of spiritual striving.
He replaced Clapton in one of the seminal British groups of the time, John Mayall’s Bluesbreakers, and in 1967 was a co-founder of Fleetwood Mac. Mr. Green named the band for two of its members — drummer Mick Fleetwood and bassist John McVie — but at the beginning, he was its undisputed leader and creative dynamo. The British music press dubbed him the “Green god.”
“Peter could have been the stereotypical superstar guitar player and control freak,” Fleetwood told the Irish Times newspaper in 2017. “But that wasn’t his style. He named the band after the bass player and drummer . . . the reason there’s a Fleetwood Mac at all is because of him.”
Rolling Stone magazine named Mr. Green one of the top 100 guitarists in rock history. One of his idols, Delta blues master B.B. King, reportedly said Mr. Green had “the sweetest tone I ever heard. He was the only one who gave me the cold sweats.”
Mr. Green’s early leadership of Fleetwood Mac was so powerful that, when the group released its first album in 1968, the record label billed it as “Peter Green’s Fleetwood Mac.” In addition to classic blues tunes by Robert Johnson and Elmore James, the album contained five songs by Mr. Green and three by its second guitarist, Jeremy Spencer. (A third guitarist, Danny Kirwan, later joined the group.)
Two other albums, “Mr. Wonderful” and “Then Play On,” followed in 1968 and 1969, respectively, both featuring Mr. Green’s compositions, singing and guitar wizardry. Music polls in Britain rated Fleetwood Mac ahead of the Beatles and the Rolling Stones.
Some of Mr. Green’s most dazzling work, however, could not be heard on the band’s first albums. “Black Magic Woman” was released in 1968 as a 45-rpm single and appeared on a 1969 compilation album before becoming a hit for Santana in 1970.
Mr. Green’s lyrical instrumental ballad “Albatross,” also from 1968, became a No. 1 hit in the United Kingdom on the strength of his sublimely controlled touch on his Les Paul guitar. The 1969 single “Oh Well,” which reached No. 2 in Britain, opened with Mr. Green’s snarling electric guitar riff and his unforgettable opening line:
Can’t help about the shape I’m in
I can’t sing, I ain’t pretty and my legs are thin
But don’t ask me what I think of you
I might not give the answer that you want me to.
After rocking out for more than two minutes, the band dramatically shifted to an elegant, cinematic mode in the second half of the song, with Mr. Green playing an almost mournful extended solo on an acoustic Spanish-style guitar, with echoes of Andres Segovia.
His final major contribution to the Fleetwood Mac canon came in 1970, with “The Green Manalishi (With The Two-Prong Crown),” a song about the evils of money that contained menacing lyrics — “The night is so black that the darkness cooks” — and even more menacing guitar lines.
During his time with Fleetwood Mac, Mr. Green grew more eccentric in his manner and dress, sometimes performing in robes, with a large cross around his neck. His experiments with hallucinogenic drugs came to a head during a European tour in March 1970, when the band arrived in Munich.
Mr. Green was met at the airport by a mysterious couple — a young woman in wire-rim glasses and a man wearing a cape. He ended up spending several days with the couple, apparently taking LSD at a castle outside Munich. When other band members tried to retrieve Mr. Green from what they described as a cult, they found him playing guitar in a frenzied fashion.
Even before then, his songs were becoming more apocalyptic, and he had implored his bandmates to give away their money and other material possessions. Fleetwood and McVie persuaded Mr. Green to rejoin the band, but he left after only two months.
“To this day,” Fleetwood said in 1996, “John [McVie] and I always say that was it. Peter Green was never the same after that.” Kirwan, Mr. Green’s fellow guitarist in the band, also took hallucinogens at the German castle, and his behavior soon became so erratic that he was forced out of the group.
Mr. Green briefly played with Fleetwood Mac in 1971, but refused to sing, then quit the band for good. He gave away his royalties, sold his guitars and began staying with friends and on doorsteps.
During the 1970s, he worked at a filling station, as a hospital attendant and as a gravedigger. In 1977, after he was arrested for threatening his accountant with a shotgun, Mr. Green was treated at a psychiatric hospital.
Meanwhile, he made a few solo records that went nowhere. In the late 1970s, Fleetwood arranged a record deal for Mr. Green that would have earned him nearly $1 million for a series of albums. At the last minute, Mr. Green refused to sign the contract.
He vanished into silence and continued treatment for mental illness. He had a short-lived marriage in the 1970s, then later lived with members of his family. His fingernails grew so long that he could not finger the chords on a guitar.
By 1995, Mr. Green was staying in the English countryside with old friends, including musician Nigel Watson. When Watson handed Mr. Green a guitar, it was the first time he had touched the instrument in a dozen years.
Slowly, some of his old facility returned. In the late 1990s, Mr. Green started a new band, called the Splinter Group. He recorded an acoustic album, “The Robert Johnson Songbook,” in 1998, and a few other albums.
He went on low-key tours of Europe and the United States, looking nothing like his old self. Once slender, with dark, curly hair and a mustache, he was now bald, clean-shaven and portly. He often strummed rhythm guitar while others performed the majestic solos he had been known for in earlier years.
In interviews, he was gentle, self-effacing and rambling.
“I was very critically ill for a while there, you might say,” he told the Los Angeles Times in 1998. “I’m not really back yet.”
Peter Allen Greenbaum was born Oct. 29, 1946, in London. His father was a tailor who later worked for the British postal service. His family, which was Jewish, adopted the name Green in the late 1940s.
While growing up in a working-class neighborhood, Mr. Green was often subjected to anti-Semitic taunts. He became engrossed in music at age 10, after an older brother brought home a guitar.
By 15, Mr. Green had left school to become an apprentice butcher, but his real focus was on music, inspired by blues and early rock-and-roll. He played bass and guitar in several bands before joining Mayall’s Bluesbreakers in 1966. A year later, with Mayall’s blessing, Mr. Green invited Fleetwood and later McVie to leave the Bluesbreakers and form Fleetwood Mac.
Over the years, Fleetwood Mac changed personnel and its musical style, becoming more of a pop-oriented band with two female singers, Stevie Nicks and Christine McVie. It became one of the most successful groups of the 1970s and 1980s, selling more than 100 million records. When Fleetwood Mac was named to the Rock and Roll Hall of Fame in 1998, Mr. Green joined Santana in a performance of “Black Magic Woman.”
Survivors include a daughter from his marriage to Jane Samuels, which ended in divorce, and a son from another relationship.
For years, Mr. Green remained a subject of enduring mystery and tragedy in Britain. He seemed to be a cautionary tale of the rock-and-roll life, like the burnout cases of Pink Floyd’s Syd Barrett or the Beach Boys’ Brian Wilson.
Musician and writer Martin Celmins published a biography of Mr. Green in 2003, and the BBC produced a documentary about his life in 2009.
After 2010, Mr. Green stopped performing in public. When Mick Fleetwood produced a star-studded London tribute concert in Mr. Green’s honor in February, he did not attend.
“I’ve been kind of dead for a long time,” Mr. Green said in 1998. “I couldn’t function at all. I really haven’t got it all together yet, but I’m working on it . . . I certainly feel a lot better when I play music, however.”
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